Q: Is it possible to update the PDA or MODEM only
A: Yes, You can update any one component independently if you have a good reason for, but remember: recommended to have consistent components

Q: Where is the bootloader tar and pit file?
A: those are not used for a Kies like update. You can find totoro*.pit and bootloader in other S5360 firmware bundles, and use if you really need it, but not necessarily needed for flashing

Q: Do I need to tick repartition?
A: NO! Leave all check-boxes as default!

Q: Wipe vs Non wipe packs?
A: Wipe pack has been build including an empty userdata partition, that way flashing a wipe pack will erase your user data.
Usually wipe packs has less issues after flashing,.......

Q: I've got no issues in the past with non wipe packs. I want to flash new firmwares by having my data untouched. Can I modify wipe pack to non wipe pack?
A: Yes: Rename PDA*.tar.md5 to *.tar, then remove the userdata.img file! Don't forget to backup, because non wipe packs sometimes leads you to boot loop, and the solution is wipe data/cache.